used to enhance particles removal from wafer surface; sonic energy at the frequency range of 10-100 kHz is applied to the liquid in which wafers are immersed; not as effective, and hence not as commonly used, as megasonic scrubbing.

megasonic agitation, megasonic scrubbing

used to enhance particle removal from wafer surface by sonic pressure; megasonic energy at the frequency in 500-1000 kHz range is applied to the liquid (typically APM cleaning solution) in which wafers are immersed; more effective and less potentially damaging to the wafer (reduced cavitation) than ultrasonic agitation; standard feature in the immersion cleaning tools.